Data DestructionHow to Erase your Hard Drive’s so that there is no data leakage from your company and so that your company and officers won’t be held

financially responsible.

By: Lloyd Albin3/9/2010

How this all got started.

• Needing to get rid of more than 3 truck loads of computers (major computer pack rat).

• Known Methods:– Re-Formatting– Re-Partitioning– Overwriting multiple times– Degaussing– Opening and breaking the platters– Cooking in oven

DoD Sanitization MethodsMethod Security Level Description

Clear Low – Reused in HouseModerate – Reuse In House

Software Overwrite

Purge Low – Reused out of HouseModerate – Reuse out of HouseHigh – Reuse in House

Degaussing or using firmware Secure Erase

Destroy Moderate – Reuse NoHigh – Reuse No or Reuse out of House

Disintegration, Pulverization, Melting, Incineration (Hard media like hard drives, memory sticks, etc.)Shredding (Flexible media like Floppy Disc’s)Reduced to nominal edge dimensions of 5mm and surface area of 25mm

Clearing StandardsMethod Times of Overwrite Lab

US DoD 5220.22-M 3 (0x00, 0xFF, Random) Low

US DoD 5220.22-M (ECE) 7 (0x00, 0xFF, Ran, 0x00, 0xFF, Ran, V-Rand) Medium

German VSITR 7 (0x00, 0xFF, 0x00, 0xFF, 0x00, 0xFF, 0xAA) Low

Russian GOST p50739-95 2 (0x00, Random) Low

Canadian OPS-II 7 (0x00, 0xFF, 0x00, 0xFF, 0x00, 0xFF, Rand) Medium

HMG IS5 Baseline 1 (0x00) Low

HMG IS5 Enhanced 3 (0x00, 0xFF, Random) Low

US Army AR380-10 3 (Random, 0x00, 0xFF) Low

US Airforce 5020 3 (0xFF, 0x00, Random) Low

Navso p-5329-26 RL (Navy) 3 (0x01, 0x27FFFFFF, Random) Low

Navso P-5329-26 MFM (Navy) 3 (0x00, 0x7FFFFFFF, Random) Low

NCSC-TG-025 3 (0x00, 0xFF, Random) Low

Bruce Schneier 7 (0xFF, 0x00, 5 Random) Medium

Roy Pfitzner 33 (33 Random) V-High

Peter Gutmann 35 (4 Random, 26 specials, 5 Random) V-High

Cleaning Software – Block Erase

• Darik’s Boot and Nukehttp://www.dban.org/

• Eraserhttp://eraser.heidi.ie/

• Active KillDiskhttp://www.killdisk.com/

• File Shredderhttp://www.fileshredder.org/

• Paragon Disk Wiper Professionalhttp://www.disk-wiper.com/

Purging StandardsMethod Times of Overwrite Lab

Secure Erase (ATA-6) 1 (Binary zeros or binary ones)Secure erase does a single on-track erasure of the data on the disk drive, after technical testing at CMRR showed that multiple on-track overwrite passes gave no additional erasure.

High

Enhanced Secure Erase (ATA-6 Optional)

1 (4 byte Vendor Pattern) High

Sanitize Device (ATA-8 Optional)

Settable + Encryption Key ChangeAES 128-bit (256-bit not possible due to US Export laws)

V-High

Degaussing Wand – Low Power – Class I

(Not effective on current hard drives.)Less than 350 Oe coercivity

Degaussing Wand – High Power – Class II

(Must open up hard drive and use directly on the platters)350-750 Oe coercivity

V-High

Degaussing – Very High Power – Class III

(No known device)Over 750 Oe coercivity

Purging Software – Secure Erase

• CCMR Secure Erase (HDDErase) http://cmrr.ucsd.edu/people/Hughes/SecureErase.shtml

• Hddparmhttp://sourceforge.net/projects/hdparm/http://hdparm-win32.dyndns.org/hdparm/

What does Secure Erase do?

• Security Set Password (F1h)• Security Freeze Lock (F5h)• Security Erase Prepare (F3h)• Security Erase Unit (F4h)• Security Unlock (F2h)• Security Disable Password (F6h)

What does Sanitize Device do?

• Sanitize Freeze Lock Ext (20h)• Sanitize Prepare (FFh) *• Sanitize Status Ext (0h)• Crypto Scramble Ext (11h)• Block Erase Ext (12h)• Overwrite Ext (14h)

Crushing and Shredding

844 grams of Thermite Destruction

References• http://cmrr.ucsd.edu/people/Hughes/CmrrSecureEraseProtocols.pdf• Peter Gutmann

http://www.cs.auckland.ac.nz/~pgut001/pubs/secure_del.html• NIST 800-88

http://csrc.nist.gov/publications/nistpubs/800-88/NISTSP800-88_rev1.pdf• http://mareichelt.de/pub/notmine/sanitizing.html• http://www.t13.org/Documents/UploadedDocuments/docs2009/d2015r2-ATAATAPI_C

ommand_Set_-_2_ACS-2.pdf

• http://ata.wiki.kernel.org/index.php/ATA_Secure_Erase• http://

www.t13.org/Documents/UploadedDocuments/docs2008/e07197r1-T13_Sanitize_Command_Proposal_Overview.pdf

• Overwriting Hard Drive Data: The Great Wiping Controversyhttp://www.springerlink.com/content/408263ql11460147/

• http://en.wikipedia.org/wiki/AT_Attachment• http://www.killdisk.com/downloads/KillDisk_Win5.pdf• http://www.seagate.com/staticfiles/support/disc/manuals/notebook/momentus/5400.

6%20(Wyatt)/100528359e.pdf

• http://www.redbooks.ibm.com/technotes/tips0761.pdf• http://

www.h-online.com/newsticker/news/item/Secure-deletion-a-single-overwrite-will-do-it-739699.html